Safety-collar for abrasive wheels.



D. B. HYDE.

SAFETY COLLAR FQB ABBASLVE WHEELS.

APPLICATION FILED 11121, 1907.

Patented July 6, 1909.

A X i MI. I. awn cm WM- mm"! a a UNITED STATES PATENT OFFICE.

DAVID B. HYDE, OF SANTA ANA, CALIFORNIA.

SAFETY-COLLAR FOR ABBASIVE WHEELS.

To all whom it may concern:

Be it known that I, DAVID B. Hrnn, a citizen of the United States,residing at Santa Ana, in the county of Orange, State of California,have invented a new and useful Safety-Collar for Abrasive heels, ofwhich the following is a specification.

This invention relates to collars to be used for emery wheels, polishingwheels, or other abrasive wheels, and the main object of the inventionis to prevent accidents to workmen by flying pieces of emery or othermaterial of which the wheel is composed. This object is secured first,by providing means which, far as possible, safeguards or prevents thewheel from breaking, and second, by providing means, which in case ofbreakage,

holds the pieces of the wheel from dying out.

In the manufacturing of emery or other abrasive grinding wheels, thesides of the wheel have to be smoothed or turned after coming from thekilns or molds. The material of which the wheel is composed and thecements of varying hardness that have to be used for wheels of differentclasses, render it very expensive and almost an impossibility to turn upthe sides of the wheel so that they are always true to each other.Moreover, the least variation in the bushings of the wheels is liable tothrow the sides out of line. In the use of safety collars on wheels withone or both sides turned convex, many wheels have been broken orstrained from the unequal pressure of the side safety collars. Thisinvention provides for safeguarding against such breakage or strainingby means of a pressure ring of rubber or other flexible material, thesurface of which bears against the sides of the wheel so that the wheelwill revolve in unison with the spindle or arbor upon which it ismounted, while at the same time the lateral strain or pressure on thesides of the wheel is equalized, compensating for inequalities ofsurface, and in combination with such equalizing pressure means Iprovide teeth or serrations surrounding said flexible material, saidteeth or serrations only coming in contact with the sides of the wheelin case of the accidental breakage of said wheel.

In the accompanying drawings :Figure 1 is an. axial section of agrinding wheel provided with my improved collars. Fig. 2 is an innerface elevation of one of the collars.

1 designates an abrasive wheel, which may be an emery or other abrasivewheel, grind- Specification of Letters Patent.

Application filed January 21, 1907.

Patented July 6, 1909.

Serial No. 353,395.

ing, or polishing wheel. Said wheel has the usual central hole 2 for thereception of the arbor or spindle 3.

A collar 4t is placed at each side of the wheel, said collar beingformed to fit more or less, the side of the wheel being concave ordished in case of a convex sided wheel, as shown. These collars havecentral holes 5 to receive the arbor 3 and are held in place by fastcollar 6 on the spindle, loose collar 7, and nut 8.

The inner face of each collar is grooved or recessed annularly as shownat 10, and also provided with inwardly projecting guard teeth orserrations 11. The projections are preferably located immediatelyadjacent to the outer wall. of each recess and thereby increase theheight of said all to the extent of the height of the serrations. Thedistance between the serrations on the opposing collars is normally lessthan the maximum thickness of the wheel 1, so that of can not moveradially from between the collars without being caught'by saidserrations. A pad or ring of elastic material, as rubber, is seated ineach groove with its inner face normally projecting inward beyond saidserrations so as to engage with the sides of the wheel 1 when thecollars are forced inward, and hold the wheel in position independentlyof the serrations.

So long as the wheel remains intact the pressure upon the cushions 10 isnot sufficient to compress them so as to permit of the engagement of theserrations with the sides of the wheel, but if the wheel should breakthe pieces would immediately be thrown outward which would cause thethicker portion of the fragments nearer the hub to be wedged in bet-weenthe opposing cushions and compress them to such an ex tent that theunyielding serrations would engage with said fragments and stop theiroutward movement. As this movement of the fragments is radial therewould be a tendency for their inclined walls to push the pads or elasticbands outward which would have a tendency to unseat them, or cause themto roll over onto the serrations, and thereby prevent the sharp edges ofthe serrations from engaging with the sides of the fragments and holdingthem fast. This outward movement of the bands is stopped, or retarded,by the higher outer wall of each recess formed by locating the serraonbreaking of the wheel the portions there.

tions immediately adjacent thereto and causing them to project inward asheretofore stated.

In operation, the wheel is clamped between the collars, the yielding orcushion members 9 engaging with the collar faces and clamping the sametightly and yet yieldingly, so that any slight deviations of the wheelsurface from uniformity will not cause strain or bending by the pressureof the collars, and pressure will not be concentrated at a fewhighpoints but will be distributed uniformly over considerable space,covered by the members 9. I thus obviate the most serious cause ofbreakage, namely, unequally distributed pressure on the wheel by thecollars.

What I claim is In a grinding and polishing wheel, the combination witha convex sided wheel, of a pair of clamping collars upon opposite sidesthereof, the inner face of each collar being concaved and recessedannularly and provided with inwardly projecting serrations immediatelyadjacent to the outer wall of each recess, the distance between saidserrations being normally less than the maximum thickness of the convexsided wheel, and an annular pad of elastic material in each recess, theinner face of which projects inward beyond said serrations and normallyholds the wheel out of engagement with said serrations, said elasticmaterial being adapted to be compressed by the outward movement of thethicker portions of the wheel until said thicker portions engage withand are held against further outward movement by said serrations.

In testimony whereof, I have hereunto set my hand at Los AngelesCalifornia this 10th day of January 1907.

DAVID B. HYDE.

In presence of- ARTHUR P. KNIGHT, FRANK L. A. GRAHAM.

